ch.aplu.nxt

Class Gear

java.lang.Object

ch.aplu.nxt.Part

ch.aplu.nxt.Gear

All Implemented Interfaces:

SharedConstants

public class Gear
extends Part

Combines two motors on an axis to perform a car-like movement.

Field Summary

Fields inherited from interface ch.aplu.nxt.SharedConstants

ABOUT, ANGLE, ANGLESTEPSMODE, BOOLEANMODE, BOOT, BRAKE, CELSIUSMODE, CLOSE, CUSTOM, DEBUG_LEVEL_HIGH, DEBUG_LEVEL_LOW, DEBUG_LEVEL_MEDIUM, DEBUG_LEVEL_OFF, DELETE, DELETE_USER_FLASH, DIRECT_COMMAND_NOREPLY, DIRECT_COMMAND_REPLY, FAHRENHEITMODE, FIND_FIRST, FIND_NEXT, GET_BATTERY_LEVEL, GET_CURRENT_PROGRAM_NAME, GET_DEVICE_INFO, GET_FIRMWARE_VERSION, GET_INPUT_VALUES, GET_OUTPUT_STATE, HIGH_SPEED_BUFFER, KEEP_ALIVE, LIGHT_ACTIVE, LIGHT_INACTIVE, LOWSPEED, LOWSPEED_9V, LS_GET_STATUS, LS_READ, LS_WRITE, MESSAGE_READ, MESSAGE_WRITE, MODEMASK, MOTOR_RUN_STATE_IDLE, MOTOR_RUN_STATE_RAMPDOWN, MOTOR_RUN_STATE_RAMPUP, MOTOR_RUN_STATE_RUNNING, MOTORON, NO_OF_SENSOR_TYPES, NO_SENSOR, NXJ_FIND_FIRST, NXJ_FIND_NEXT, OPEN_APPEND_DATA, OPEN_READ, OPEN_READ_LINEAR, OPEN_WRITE, OPEN_WRITE_DATA, OPEN_WRITE_LINEAR, PCTFULLSCALEMODE, PERIODCOUNTERMODE, PLAY_SOUND_FILE, PLAY_TONE, POLL, POLL_BUFFER, POLL_LENGTH, RAWMODE, READ, REFLECTION, REGULATED, REGULATION_MODE_IDLE, REGULATION_MODE_MOTOR_SPEED, REGULATION_MODE_MOTOR_SYNC, REPLY_COMMAND, RESET_MOTOR_POSITION, RESET_SCALED_INPUT_VALUE, SET_BRICK_NAME, SET_INPUT_MODE, SET_OUTPUT_STATE, SLOPEMASK, SOUND_DB, SOUND_DBA, START_PROGRAM, STOP_PROGRAM, STOP_SOUND_PLAYBACK, SWITCH, SYSTEM_COMMAND_NOREPLY, SYSTEM_COMMAND_REPLY, TEMPERATURE, TITLE, TITLEMP, TRANSITIONCNTMODE, VERSION, WRITE

Constructor Summary

Constructors

Constructor and Description
Gear() Creates a gear instance with left motor plugged into port A, right motor plugged into port B.
Gear(MotorPort port1, MotorPort port2) Creates a gear instance with right motor plugged into port1, left motor plugged into port2.

Method Summary

Methods

Modifier and Type	Method and Description
void	addMotionListener(MotionListener motionListener) Register the given motion listener.
Gear	backward() Same as forward(), but move in reverse direction.
Gear	backward(int duration) Same as forward(int duration), but move in reverse direction.
Gear	forward() Starts the forward movement with preset speed.
Gear	forward(int duration) Starts the forward movement for the given duration (in ms) with preset speed.
Motor	getMotLeft() Returns left motor of the gear.
Motor	getMotRight() Returns right motor of the gear.
int	getSpeed() Returns the current speed (arbitrary units).
double	getVelocity() Returns the current velocity.
boolean	isMoving() Checks if one or both motors are rotating.
Gear	left() Starts turning left with left motor stopped and right motor at preset speed.
Gear	left(int duration) Starts turning left for the given duration (in ms) with preset speed.
Gear	leftArc(double radius) Starts turning to the left on an arc with given radius (in m).
Gear	leftArc(double radius, int duration) Starts turning to the left on an arc with given radius (in m) for the given duration (in ms) with preset speed.
Gear	moveTo(int count) Same as moveTo(int count, boolean blocking) with blocking = true.
Gear	moveTo(int count, boolean blocking) Sets the rotation counter to zero and rotate both motors until the given count is reached.
Gear	right() Same as left(), but turns in the opposite direction.
Gear	right(int duration) Same as left(int duration), but turning in the opposite direction.
Gear	rightArc(double radius) Same as leftArc(double radius), but turns in the right.
Gear	rightArc(double radius, int duration) Same as leftArc(double radius, int duration), but turns to the right.
Gear	setSpeed(int speed) Sets the speed to the given value (arbitrary units).
Gear	setVelocity(double velocity) Sets the velocity to the given value.
Gear	stop() Stops the gear.
Gear	turnTo(int count) Same as turnTo(int count, boolean blocking) with blocking = true.
Gear	turnTo(int count, boolean blocking) Sets the rotation counter to zero and turn with the motors running in opposite direction.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Gear

public Gear(MotorPort port1,
    MotorPort port2)

Creates a gear instance with right motor plugged into port1, left motor plugged into port2.

Parameters:

port1 - MotorPort.A or MotorPort.B or MotorPort.C (not both the same)

port2 - MotorPort.A or MotorPort.B or MotorPort.C (not both the same)

Gear

public Gear()

Creates a gear instance with left motor plugged into port A, right motor plugged into port B.

Method Detail

getSpeed

public int getSpeed()

Returns the current speed (arbitrary units).

Returns:

speed 0..100

getVelocity

public double getVelocity()

Returns the current velocity. The velocity in m/s with some inaccuracy.
velocity = MotorSpeedFactor * speed (default: MotorSpeedFactor set in NxtLib.properties).

Returns:

velocity in m/s

setSpeed

public Gear setSpeed(int speed)

Sets the speed to the given value (arbitrary units). The speed will be changed to the new value at the next movement call only.

Parameters:

speed - 0..100

Returns:

the object reference to allow method chaining

setVelocity

public Gear setVelocity(double velocity)

Sets the velocity to the given value. The velocity will be changed to the new value at the next movement call only.
velocity = MotorSpeedFactor * speed (default MotorSpeedFactor set in NxtLib.properties).

Parameters:

velocity - in m/s

Returns:

the object reference to allow method chaining.

stop

public Gear stop()

Stops the gear. (If gear is already stopped, returns immediately.)

Returns:

the object reference to allow method chaining.

moveTo

public Gear moveTo(int count,
          boolean blocking)

Sets the rotation counter to zero and rotate both motors until the given count is reached. If count is negative, the motors turn backwards. If blocking = false, the method returns immediately. You may register a motion listener with addMotionListener() to get a callback when the count is reached and the motors stop. If blocking = true, the method returns when the count is reached and the motors stop.
The motors start smoothly if the speed is not too fast.

Returns:

the object reference to allow method chaining

See Also:

addMotionListener(MotionListener motionListener), moveTo(int count)

moveTo

public Gear moveTo(int count)

Same as moveTo(int count, boolean blocking) with blocking = true.

See Also:

moveTo(int count, boolean blocking)

turnTo

public Gear turnTo(int count)

Same as turnTo(int count, boolean blocking) with blocking = true.

See Also:

turnTo(int count, boolean blocking)

turnTo

public Gear turnTo(int count,
          boolean blocking)

Sets the rotation counter to zero and turn with the motors running in opposite direction. If count is positive, turns clockwise, otherwise anti-clockwise (MotorPort.A is right, MotorPort.B is left motor). If blocking = false, the method returns immediately. If blocking = true, the method returns when the count is reached and the motors stop.

Returns:

the object reference to allow method chaining.

See Also:

turnTo(int count)

addMotionListener

public void addMotionListener(MotionListener motionListener)

Register the given motion listener. When calling moveTo() a motion detector thread is started that checks the motion of the motors. When the motion stops because the rotation count is reached or stop() is called, the MotionListener's callback motionStopped() is invoked and the motion detector thread terminates.

Parameters:

motionListener - the MotionListener to be registered

forward

public Gear forward()

Starts the forward movement with preset speed. Method returns, while the movement continues. (If gear is already moving forward, returns immediately.)

Returns:

the object reference to allow method chaining.

forward

public Gear forward(int duration)

Starts the forward movement for the given duration (in ms) with preset speed. Method returns at the end of the given duration, but the movement continues for 200 ms. Then it stops unless another movement method call (forward, backward, left, right, leftArc, rightArc) is invoked within that time. Calling several movement methods one after the other will result a seamless movement without intermediate stops.
To use it without problems in a callback method, it returns quickly when LegoRobot.disconnect is called.

Parameters:

duration - the duration (in ms)

Returns:

the object reference to allow method chaining

backward

public Gear backward()

Same as forward(), but move in reverse direction.

See Also:

forward()

backward

public Gear backward(int duration)

Same as forward(int duration), but move in reverse direction.

See Also:

forward(int duration)

left

public Gear left()

Starts turning left with left motor stopped and right motor at preset speed. Method returns, while the movement continues. (If gear is already turning left, returns immediately.)

Returns:

the object reference to allow method chaining

left

public Gear left(int duration)

Starts turning left for the given duration (in ms) with preset speed. Method returns at the end of the given duration but the movement continues for 200 ms. Then it stops unless another movement method call (forward, backward, left, right, leftArc, rightArc) is invoked within that time. Calling several movement methods one after the other will result a seamless movement without intermediate stops.

Parameters:

duration - the duration (in ms)

Returns:

the object reference to allow method chaining

right

public Gear right()

Same as left(), but turns in the opposite direction.

See Also:

left()

right

public Gear right(int duration)

Same as left(int duration), but turning in the opposite direction.

See Also:

left(int duration)

leftArc

public Gear leftArc(double radius)

Starts turning to the left on an arc with given radius (in m). If the radius is negative, turns left backwards. The accuracy is limited and depends on the distance between the two wheels (default: AxeLength set in NxtLib.properties). Method returns, while the movement continues. (If gear is already moving on an arc with given radius, returns immediately.)

Parameters:

radius - the radius of the arc (in m)

Returns:

the object reference to allow method chaining

leftArc

public Gear leftArc(double radius,
           int duration)

Starts turning to the left on an arc with given radius (in m) for the given duration (in ms) with preset speed. If the radius is negative, turns left backwards. The accuracy is limited and depends on the distance between the two wheels (default: AxeLength set in NxtLib.properties). Method returns at the end of the given duration but the movement continues for 200 ms. Then it stops unless another movement method call (forward, backward, left, right, leftArc, rightArc) is invoked within that time. Calling several movement methods one after the other will result a seamless movement without intermediate stops.

Parameters:

radius - the radius of the arc (in m)

duration - the duration (in ms)

Returns:

the object reference to allow method chaining

rightArc

public Gear rightArc(double radius)

Same as leftArc(double radius), but turns in the right.

See Also:

leftArc(double radius)

rightArc

public Gear rightArc(double radius,
            int duration)

Same as leftArc(double radius, int duration), but turns to the right.

See Also:

leftArc(double radius, int duration)

getMotRight

public Motor getMotRight()

Returns right motor of the gear.

Returns:

the reference of the right motor

getMotLeft

public Motor getMotLeft()

Returns left motor of the gear.

Returns:

the reference of the left motor

isMoving

public boolean isMoving()

Checks if one or both motors are rotating.

Returns:

true, if gear is moving, otherwise false